Diagnostic systems are used by technicians and professionals in virtually all industries to perform basic and advanced system testing functions. For example, in the automotive, trucking, heavy equipment and aircraft industries, diagnostic test systems provide for vehicle onboard computer fault or trouble code display, interactive diagnostics, multiscope and multimeter functions, and electronic service manuals. In the medical industry, diagnostic systems provide for monitoring body functions and diagnosis of medical conditions, as well as system diagnostics to detect anomalies in the medical equipment.
In many industries, diagnostic systems play an increasingly important role in manufacturing processes, as well as in maintenance and repair throughout the lifetime of the equipment or product. Some diagnostic systems are based on personal computer technology and feature user-friendly, menu-driven diagnostic applications. These systems assist technicians and professionals at all levels in performing system diagnostics on a real-time basis.
A typical diagnostic system includes a display on which instructions for diagnostic procedures are displayed. The system also includes a system interface that allows the operator to view real-time operational feedback and diagnostic information. Thus, the operator may view, for example, vehicle engine speed in revolutions per minute, or battery voltage during start cranking; or a patient's heartbeat rate or blood pressure. With such a system, a relatively inexperienced operator may perform advanced diagnostic procedures and diagnose complex operational or medical problems.
The diagnostic procedures for diagnostic systems of this sort are typically developed by experienced technical experts or professionals. The technical expert or professional provides the technical experience and knowledge required to develop complex diagnostic procedures. However, the diagnostic procedures generally are oriented toward beginning with a symptom and identifying the cause, or failure mode, of the symptom.
Thus, existing diagnostic systems have a disadvantage in that the diagnostic test procedures focus on beginning from a symptom and diagnosing a failure mode that is the cause of the symptom. As a result, the diagnostic test procedures of existing diagnostic systems generally do not correlate all of the possible symptoms of a particular failure mode, or of a particular vehicle component, with the corresponding failure mode or component. Accordingly, it is desirable to provide a method and apparatus for reverse failure analysis of diagnostic test procedures to identify all of the known or possible symptoms that can be associated with a failure mode or with a vehicle component, and for correlating the symptoms with the corresponding failure mode or component.